biostudies-literatureSmirnoff NBiotechnology and Biological Sciences Research Council2604-2630https://www.ebi.ac.uk/biostudies/studies/S-EPMC11066809biostudies-literatureUnknown75(9)Ascorbate (vitamin C) is one of the most abundant primary metabolites in plants. Its complex chemistry enables it to function as an antioxidant, as a free radical scavenger, and as a reductant for iron and copper. Ascorbate biosynthesis occurs via the mannose/l-galactose pathway in green plants, and the evidence for this pathway being the major route is reviewed. Ascorbate accumulation is leaves is responsive to light, reflecting various roles in photoprotection. GDP-l-galactose phosphorylase (GGP) is the first dedicated step in the pathway and is important in controlling ascorbate synthesis. Its expression is determined by a combination of transcription and translation. Translation is controlled by an upstream open reading frame (uORF) which blocks translation of the main GGP-coding sequeJournal of experimental botanyThe ascorbate biosynthesis pathway in plants is known, but there is a way to go with understanding control and functions.PMC11066809BB/W006553/1Wheeler GLSmirnoff NfalseThe ascorbate biosynthesis pathway in plants is known, but there is a way to go with understanding control and functions.Ascorbate (vitamin C) is one of the most abundant primary metabolites in plants. Its complex chemistry enables it to function as an antioxidant, as a free radical scavenger, and as a reductant for iron and copper. Ascorbate biosynthesis occurs via the mannose/l-galactose pathway in green plants, and the evidence for this pathway being the major route is reviewed. Ascorbate accumulation is leaves is responsive to light, reflecting various roles in photoprotection. GDP-l-galactose phosphorylase (GGP) is the first dedicated step in the pathway and is important in controlling ascorbate synthesis. Its expression is determined by a combination of transcription and translation. Translation is controlled by an upstream open reading frame (uORF) which blocks translation of the main GGP-coding seque2024-01-01T00:00:00Z2024 May2026-05-29T12:21:27.122Z2026-05-19T03:07:22.374ZS-EPMC110668093830023710.1093/jxb/erad505